Research Advances in Excited State Intramolecular Proton Transfer Fluorescent Probes Based on Combined Fluorescence Mechanism

Abstract Fluorescent probes can achieve rapid detection of analytes, and have become a research hotspot in recent years due to their excellent selectivity, high sensitivity and easy operation. Excited state intramolecular proton transfer (ESIPT) is one of the most basic strategies for designing fluorescence probes. Fluorescent probes based on ESIPT possess large Stokes shift, strong luminescence and high fluorescence quantum yield. However, these are still some disadvantages, such as sensitivity to the environment and short emission wavelength. In recent years, the ESIPT combined with other fluorescence mechanisms, can obtain new fluorescent probes with dual mechanism of fluorescence response. This strategy can not only solve the shortage of ESIPT fluorophore, but also realize multi-fluorescence signal channel, and significantly improve the selectivity and sensitivity of the new probe. In this review, we mainly summarized the detection mechanism and imaging application of fluorescence probes of PET-ESIPT, ICT-ESIPT, FRET-ESIPT, AIE-ESIPT for ions, small molecules, biological macromolecules in recent years.